Detonator



July 1966 P. BEERMANN ETAL 3,260,206

DETONATOR Filed Feb. 15, 1964 INVENTORS:

F L Beermcmn & 3 I WLLLL Gvoss-Benne ATTORNEYS United States Patent Filed Feb. 13, 1964, Ser. No. 344,647 Claims priority, application Germany, Feb. 13, 1963, R 25,550; Mar. 4, 1963, R 25,665; Aug. 9, 1963,

8 Claims. (Cl. 102-70 The present invention relates generally to the firearms art, and, more particularly, to a detonator having a firing pin for igniting fuse cords, delayed action tubes such as a friction igniter, and for igniting blasting caps imbedded in explosive charges.

Detonators of various constructions which are technically satisfactory in function are known. However, many times there is a disadvantage due to their relatively high cost of construction in that the interior mechanism is constructed of complicated machined, lathed, or punched parts, the manufacture of which is accompanied by high tolerance requirements so that the production of such detonators involves relatively high costs.

With these defects of the prior art in mind, it is a main object of the present invention to provide a detonator having a firing pin and which is technically satisfactory in operation, and safe in handling, while also being capable of being manufactured in a simple and inexpensive manner.

Another object of the present invention is to provide a device of the character described which may be adapted for use with various detonator constructions.

A further object of the invention is to provide a device of the above-mentioned type which has a safely functioning and simply constructed stationary mounting for a fuse cord.

Still a further object is to provide a detonator construction which is properly sealed before use but which nevertheless properly vents the combustion gases upon operation of the device.

These objects and others ancillary thereto are accomplished in accordance with preferred embodiments of the invention wherein a detonator is. constructed having a housing arranged in the form of a hollow cylinder. A firing pin disposed for axial movement is positioned within the housing and a spring is provided for tensioning the firing pin. A blocking or suppressing member secures the firing pin against spring pressure and the firing pin can be cocked by displacing the blocking member. A primer may be imbedded within the detonator housing as may a firing mechanism. The firing pin is provided with a flange against which the firing pin spring abuts and the other end of the spring abuts against the bottom of the detonator housing. The firing pin is also provided with a constricted portion and the blocking member or suppressor member engages this constricted portion. The blocking member may slide, when the firing pin mechanism is pulled and after the firing pin is cocked, along inclined or oblique surfaces provided on the constriction and the blocking member may by this means be moved into its released position.

The detonator housing in a suitable manner carries an exterior thread at one end for insertion into an explosive charge, and also preferably is provided with an interior thread for threading a delayed action tube into the housing which may extend into an explosive charge. At the other end of the housing the detonator carries a firing mechanism and is provided here with an exterior thread for mounting a wing nut useful for handling the device and for mounting a cap for protecting the firing mechanism.

Additional objects and advantages of the present invention will become apparent upon consideration of the following description when taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a longitudinal sectional view of a friction igniter having a delayed action tube.

FIGURE 2 is a longitudinal sectional view of the detonator of the present invention arranged for igniting a fuse cord.

FIGURE 3 is a longitudinal sectional view illustrating a first step in the construction of a slight modification of the FIGURE 2 arrangement.

FIGURE 4 is a longitudinal sectional view showing the final step in the construction of this modified arrangement.

Before referring to the drawings in detail, it should be noted that the present invention provides a safely functioning and simple construction of a stationary fuse cord mounting. This is accomplished by using a sealing stopper as the blocking member which is disposed within an enlarged cavity of the substantially hollow and cylindrical detonator housing. This cavity opens toward the exterior side of the device and the stopper is connected with the firing mechanism. The end of the firing pin which is provided with the constriction is engaged by the stopper in a sealing manner and the stopper is completely or partially divided in a longitudinal direction into at least two portions and is provided with recesses in the halves of the stopper which conform to the constricted end of the firing pin. Also, the firing pin spring is arranged to have a slight pretensioning.

Furthermore, the sealing stopper which serves as the blocking member for suppressing the firing pin is provided exteriorly of the detonator housing with means for fastening a triggering cord which is connected with a cap which may be tightly threaded onto the detonator housing. The connection of the triggering cord with the suppressing member may be accomplished, for example, by means of a transverse bore in the latter.

Another feature of the invention provides a fixed fuse cord mounting which includes an elastic tube of rubber or the like and includes a cap screw or sleeve for causing a deformation and thus buckling of the tube. The tube is suitably placed onto the end of the fuse cord inserted into the detonator housing with a certain amount of play and when there is buckling of the tube it constricts and suitably holds the fuse cord in place.

Because of the above-mentioned features, an additional sealing of the cavity of the detonator housing in the area of the constricted firing pin end is not needed. Furthermore, the novel blocking member and the cylindrical firing pin can be manufactured inexpensively and the former, for example, can be constructed by extrusion or the like of plastic and the latter by lathing on an automatic lathe. Also, a trouble-free ignition or burning, for ex ample, of a delayed action tube is assured because. after the simple device of the present invention is ignited, the stopper which serves as the blocking member is pulled out of the detonator housing completely and the combustion gases can then freely exit from the detonator housing. The above-mentioned feature of the fixed mounting of a fuse cord end inserted into the detonator housing assures that there will be a safe fastening of the end of the fuse cord as well as a waterproof connection of the fuse cord to the detonator. Thus, a damaging of the fuse cord is precluded due to this fixed mounting. In addition, the fuse cord can be inserted and fastened in the detonator housing conveniently and quickly for the purposes of coupling the cord to the device of the present invention.

With more particular reference to the drawings, it may be noted that a firing pin 2 is mounted for axial movement interiorly of a hollow detonator housing 1. The firing pin is provided with a reduced portion 3 near one main portion of the firing pin and a tapered section 3b on the end portion of the firing pin. A flange 2a is provided on the firing pin near its striking end and a firing pin spring 4 is also disposed within the housing and is mounted to have a slight pretensioning. The spring 4 surrounds the body of the firing pin and extends between an upper partition 1b of the body and the flange on the firing pin to bias it in a downward direction. The firing pin passes through an opening 10 in this partition.

The firing pin is provided with a bifurcated lower end 6 which is needed for igniting the primer 5. This firing pin 2 is fixedly mounted in a two-piece sealing stopper or suppressor 7 which is tightly pressed into an enlarged interior cavity portion 1a of the housing 1. Variation of the force to be used for triggering the detonator may be provided by more or less tightly pressing the stopper 7 into place in the cavity In. This suppressor 7 is of a material capable of deforming and its surrounds and holds in place the end of the firing pin which includes reduced portion 3. The primer is mounted in a nipple 8 which is threaded into the detonator housing. A wing nut 8a and a cap 9 which is tightly screwed into place are provided at the head of the detonator. A triggering cord 10 and a blocking disc 11 are disposed within the cap 9 and the peripheral dimensions of disc 11 are such that it can not be pulled out of the opening in cap 9. The trigger cord 10 passes through a transverse 'bore 7a in suppressor 7 so when the cord is pulled the suppressor will release the firing pin.

A delayed action tube 12 is threaded into the housing 1 and is tightly surrounded by a nipple 14 which is threaded onto the housing and which is provided with a protective cap 13 at its end as well as a paraffin seal 13a. The detonator is sealed by means of a clear lacquer between the nipple 14 and the detonator housing 1 and between Wing nut 8a and the housing at those places indicated at X. If desired, a blasting cap may be provided in place of a delayed action tube 12.

In operation, the cap 9 is unscrewed and by pulling at this cap the stopper or suppressor 7 together with the firing pin 2 is pulled upwardly by means of the trigger cord 10 and the firing pin spring 4 is further tensioned. When the firing spin spring is tensioned a certain amount, the stopper 7 will be withdrawn from the enlarged cavity 1a of the detonator housing 1 and will come apart. Thus, the firing pin becomes free and because of the spring pressure of the firing pin spring 4 the pin is released and strikes the primer 5 which is fitted within the nipple 8. During this detonating process, the detonating gases may exit freely upwardly as the stopper at the timer of triggering is pulled completely out of the detonator housing and no longer closes opening 10 in partition 1b.

The individual portions of the detonator may be constructed of metallic material as well as of impact-resistant and tem erature-constant synthetic materials. For production purposes, it is always suitable to make the twopart stopper 7 of a plastic material.

In FIGURE 2, elements which are similar to those of FIGURE 1 are provided with identical reference numerals. It may be noted that a hollow cap screw or sleeve 15 is threaded onto the detonator housing 1. An elastic tube 17 of rubber or of a synthetic elastic material is fixedly mounted within the cap screw 15 by means of snap rings and/or discs 16, and seals 18 are also provided in the cap screw. Furthermore, the nipple 8 which carries the primer 5 is supported in place by a clamping ring 19.

In the device shown in FIGURES 3 and 4, a sleeve 21 is threaded onto the detonator housing and is provided with a threaded ring 22 and an elastic tube 17 which is provided for fixedly mounting the end of a fuse cord. The outer diameter of the tube 17 when it is not deformed (see FIGURE 3) is equal to or smaller than the minor thread diameter of the threaded ring 22.

After the fuse cord 20 is inserted into the screw connection, the socket 21 is further threaded onto the conmeeting thread of the detonator housing 1 (FIGURES 3 and 4), or the cap screw 15 is further threaded onto the connecting thread of the housing (FIGURE 2). The length of the threaded portion of the detonator is longer than the length of the threads in the socket 21. Because of this, the tube 17 is deformed and buckles so that, as illustrated in FIGURE 4, it is bent and constricted until it engages the end 20 of the fuse cord. In this manner the fuse cord is tightly connected with the detonator. Furthermore, a waterproof connection is also provided. In addition, the diameter of the fuse cord may vary within wide limits.

The screw connection could be constructed of plastic materials or of temperature-constant impact-resistance plastic. A caoutchouc or rubber-like mass or plastic material having the desired and necessary elasticity can be used for the tube which should also remain constant under temperature variations.

It will be understood that the above-description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

What is claimed is:

1. A detonator device, comprising, in combination:

a hollow cylindrical detonator housing having an exterior thread on one end for insertion into an exposive charge and also having an interior thread for threadedly mounting a delayed action tube extending into an explosive charge, and the other end of said housing having an exterior thread;

a firing pin in said housing and mounted for axial movement therein, said firing pin having a flange thereon, and a reduced portion near one end thereof having inclined surfaces directed outwardly from said reduced portion toward said one end of said firing P a firing pin spring disposed between said firing pin flange and a portion of said detonator housing;

a firing pin suppressing member disposed in an enlarged cavity in said detonator housing, which cavity opens to the atmosphere, said one end of said firing pin normally projecting into said cavity, said suppressing member including an at least partially divided deformable stopper member engaging the reduced end portion of said firing pin and seated in said cavity in a sealing manner for normally retaining the firing pin with its said reduced portion within said cavity;

a primer in said detonator housing, said primer being spaced adjacent to the other end of said firing pin; and

a firing mechanism at said other end of said housing and including a wing nut and cap threaded to said other housing end for sliding said suppressing member out of said cavity, when actuated, whereby said suppressing member slides along the inclined surfaces of said reduced portion and thereby tension the firing pin spring by retracting the firing pin until said suppressing member comes out of the cavity and releases the firing pin whereby said firing pin spring urges said firing pin to strike said primer.

2. A device as defined in claim 1 wherein said firing pin is normally slightly pretensioned when the suppressing member holds the firing pin in position with its said reduced portion within said cavity.

3. A device as defined in claim 1 wherein said firing mechanism includes a trigger cord connected with said cap, and said suppressing member has means for fastening the trigger cord thereto.

4. A device as defined in claim 3 wherein said means is a transverse bore formed through said suppressing member.

5. A detonator device, comprising, in combination:

a hollow cylindrical detonator housing having an exterior thread on one end for insertion into an explosive charge and also having an interior thread for threadedly mounting a delayed action tube extending into an explosive charge, and the other end of said housing having an exterior thread;

a firing pin in said housing and mounted for axial movement therein, said firing pin having a flange thereon, and a reduced portion near one end thereof having inclined surfaces directed outwardly from said reduced portion toward said one end of said firing pin;

a firing pin spring disposed between said firing pin flange and a portion of said detonator housing;

a firing pin suppressing member disposed in an enlarged cavity in said detonator housing, which cavity opens to the atmosphere, said one end of said firing pin normally projecting into said cavity, said suppressing member including an at least partially divided stopper member engaging the reduced end portion of said firing pin and seated in said cavity in a sealing manner for normally retaining the firing pin with its said reduced portion within said cavity;

a primer in said detonator housing, said primer being spaced adjacent to the other end of said firing pin; a firing mechanism at said other end of said housing and including a wing nut and cap threaded to said other housing end for sliding said suppressing member out of said cavity, when actuated, whereby said suppressing member slides along the inclined surfaces of said reduced portion and thereby tensions the firing pin spring by retracting the firing pin until said suppressing member comes out of the cavity and releases said firing pin whereby said firing pin spring urges said firing pin to strike said primer; and

a fixed fuse cord mounting disposed on the opposite side of the primer from the firing pin and including an elastic tube, an end of a fuse cord disposed within said tube, a cap screw in which said tube and fuse cord end are disposed, said fuse cord being a smaller diameter than the inner diameter of said elastic tube so that it may be inserted into said tube, said cap screw being mounted for movement on said end of said detonator housing whereby movement of the cap screw toward said other end of said detonator housing causes deformation of and thus constriction of said elastic tube so that it may tightly engage said fuse cord.

6. In a detonator device having a hollow cylindrical detonator housing having, on one end thereof, an exterior thread for insertion into an explosive charge and an interior thread for threadedly mounting a delay action tube extending into an explosive charge, and the other end of the housing having an exterior thread, a firing pin in said housing and mounted for axial movement therein, said firing pin having a flange thereon, and a reduced portion near one end thereof having inclined surfaces directed outwardly from said reduced portion toward said one end of said firing pin, a firing pin spring disposed between said firing pin flange and a portion of said detonator housing, a firing pin suppressing member engaging said reduced portion of said firing pin, a primer in said detonator housing, and a firing mechanism at said other end of said housing and including a wing nut and cap threaded to said other housing end, the improvement wherein said suppressing member is disposed in an enlarged cavity in said detonator housing, which cavity opens to the atmosphere, said one end of said firing pin normally projecting into said cavity, said suppressing member including an at least partially divided deformable stopper seated in said cavity in a sealing manner for normally retaining the firing pin with its said reduced portion within said cavity, said nut and cap being connected to be capable of sliding said suppressing member out of said cavity whereby said suppressing member slides along the inclined surfaces of said reduced portion and thereby tensions said firing pin spring by retracting said firing pin until said suppressing member comes out of said cavity and releases said firing pin whereby said firing pin spring urges said firing pin to strike said primer.

7. A detonator device, comprising, in combination:

a hollow cylindrical detonator housing adapted on one end for insertion into an explosive charge;

a firing pin in said housing and mounted for axial movement therein, said firing pin having spring abutting means thereon, and a reduced portion near one end thereof having inclined surfaces directed outwardly toward said one end of said firing pin from said reduced portion;

a firing pin spring disposed between said spring abutting means and a portion of said detonator housing;

a firing pin suppressing member disposed in a cavity in said detonator housing, which cavity opens to the atmosphere, said one end of said firing pin normally projecting into said cavity, said suppressing member including an at least partially divided deformable stopper member engaging said reduced portion of said firing pin and seated in said cavity in a sealing manner for normally retaining said firing pin with its said reduced portion within said cavity;

a primer in said detonator housing, said primer being spaced adjacent to the other end of said firing pin; and

a firing mechanism at the other end of said housing and including a cap removably connected to said other end of said housing for sliding said suppressing member out of said cavity when actuated, whereby said stopper member slides along said inclined surfaces of said reduced portion and thereby tensions said firing pin spring by retracting said firing pin until said suppressing member comes out of said cavity and releases said firing pin whereby said firing pin spring urges said firing pin to strike said primer.

8. A detonator device, comprising, in combination:

a hollow cylindrical detonator housing having an exterior thread on one end for insertion into and explosive charge and also having an interior thread for threadedly mounting a delayed action tube extending into an explosive charge, and the other end of said housing having an exterior thread, said housing having an interior transverse partition with an opening therethrough to form a housing chamber on one side of said partition and an enlarged cavity open to the atmosphere on the other side of said partition;

a firing pin in said housing chamber and mounted for axial movement therein, said firing pin having a flange thereon, and a reduced portion near one end thereof having inclined surfaces directed outwardly toward said one end of said firing pin from said reduced portion;

a firing pin spring disposed between said firing pin flange and said partition;

a firing pin suppressing member disposed in said cavity, said one end of said firing pin normally projecting through said partition opening and into said cavity, said suppressing member including a deformable two part stopper member engaging and at least partially surrounding said reduced portion of said firing pin and seated in said cavity in a manner which seals said partition opening for normally retaining said firing pin with its said reduced portion within said cavity;

a primer in said detonator housing chamber, said primer being spaced adjacent to the other end of said firing P and a firing mechanism at said other end of said housing and including a wing nut and cap threaded to said other end of said housing for sliding said suppressing member out of said cavity when actuated, whereby said suppressing member slides along said inclined surfaces of said reduced portion and thereby tensions said firing pin spring by retracting said firing pin until said suppressing member comes out of said cavity and vents said chamber to the atmosphere and releases said firing pin whereby said firing pin spring 5 urges said firing pin to strike said primer.

References Cited by the Examiner UNITED STATES PATENTS 1,319,103 10/1919 Miller 102-65.

8 1,675,118 6/1928 Lucas 10270 1,792,023 2/1931 Macy 1028 2,075,813 4/1937 King 10270 2,935,949 5/1960 Holford 10270 FOREIGN PATENTS 116,214 4/ 1946 Sweden.

BENJAMIN A. BORCHELT, Primary Examiner.

4 10 R. V. LOTTMANN, Assistant Examiner. 

1. A DETONATOR DEVICE, COMPRISING, IN COMBINATION: A HOLLOW CYLINDRICAL DETONATOR HOUSING HAVING AN EXTERIOR THREAD ON ONE END FOR INSERTION INTO AN EXPLOSIVE CHARGE AND ALSO HAVING AN INTERIOR THREAD FOR THREADEDLY MOUNTING A DELAYED ACTION TUBE EXTENDING INTO AN EXPLOSIVE CHARGE, AND THE OTHER END OF SAID HOUSING HAVING AN EXTERIOR THREAD; A FIRING PIN IN SAID HOUSING AND MOUNTING FOR AXIAL MOVEMENT THERIN, SAID FIRING PIN HAVING A FLANGE THEREON, AND A REDUCED PORTION NEAR ONE END THEREOF HAVING INCLINED SURFACES DIRECTED OUTWARDLY FROM SAID REDUCED PORTION TOWARD SAID ONE END OF SAID FIRING PIN; A FIRING PIN SPRING DISPOSED BETWEEN SAID FIRING PIN FLANGE AND A PORTION OF SAID DETONATOR HOUSING; A FIRING PIN SUPPRESSING MEMBER DISPOSED IN AN ENLARGED CAVITY IN SAID DETONATOR HOUSING, WHICH CAVITY OPENS TO THE ATMOSPHERE, SAID ONE END OF SAID FIRING PIN NORMALLY PROJECTING INTO SAID CAVITY, SAID SUPPRESSING MEMBER INCLUDING AN AT LEAST PARTIALLY DIVIDED DEFORMABLE STOPPER MEMBER ENGAGING THE REDUCED END PORTION OF SAID FIRING PIN AND SEATED IN SAID CAVITY IN A SEALING MANNER FOR NORMALLY RETAINING THE FIRING PIN WHICH ITS SAID REDUCED PORTION WITHIN SAID CAVITY; A PRIMER IN SAID DETONATOR HOUSING, SAID PRIMER BEING SPACED ADJACENT TO THE OTHER END OF SAID FIRING PIN; AND A FIRING MECHANISM AT SAID OTHER END OF SAID HOUSING AND INCLUDING A WING NUT AND CAP THREADED TO SAID OTHER HOUSING END FOR SLIDING SAID SUPPRESSING MEMBER OUT OF SAID CAVITY, WHEN ACTUATED WHEREBY SAID SUPPRESSING MEMBER SLIDES ALONG THE INCLINED SURFACES OF SAID REDUCED PORTION AND THEREBY TENSION THE FIRING PIN SPRING BY RETRACTING THE FIRING PIN UNTIL SAID SUPPRESSING MEMBER COMES OUT OF THE CAVITY AND RELEASES THE FIRING PIN WHEREBY SAID FIRING PIN SPRING URGES AND FIRING PIN TO STRIKE SAID PRIMER. 